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101.
102.
Parental smoking data have been reabstracted from the interview records of the Oxford Survey of Childhood Cancers (deaths from 1971 to 1976). Reported smoking habits for the parents of 2587 children who died with cancer were compared with similar information for the parents of 2587 healthy controls (matched pairs analysis). Maternal daily consumption of cigarettes and paternal use of pipes or cigars were unimportant, but there was a statistically significant positive trend between paternal daily consumption of cigarettes and the risk of childhood cancer (P < 0.001). This association could not be explained by maternal smoking, social class, parental ages at the birth of the survey child, sibship position or obstetric radiography. Relations between maternal consumption of cigarettes and birth weights suggested that (maternal) smoking data were equally reliable for case and control subjects. About 14% of all childhood cancers in this series could be attributable to paternal smoking. These data were combined with smoking data from two previously published reports from the Oxford Survey (deaths from 1953 to 1955, deaths from 1977 to 1981) to obtain further information on risks for different types of cancer and different ages at onset of disease. Paternal cigarette smoking emerged as a potential risk factor both for the generality of childhood cancer and for all ages at onset.  相似文献   
103.
BACKGROUND: Attempts to modify traditional fluid resuscitation have been based on animal models that evaluate several variables including anesthesia. This study presents the effects of early saline resuscitation from severe uncontrolled hemorrhage unanesthetized rats. METHODS: Sixty-three female Sprague-Dawley rats were equally divided into three groups: group A, nonresuscitated; and groups B and C, resuscitated ;with isotonic saline (40 and 80 mL/kg, respectively). Hemodynamics, blood loss, survival time, and mortality were recorded for 360 minutes after the hemorrhage, which was initiated by 75% resection of the tail. RESULTS: In group C, 80 mL/kg of saline significantly lowered mortality (24% vs 76% and 71% for groups A and B, respectively) with concomitant increases in mean survival time (241 +/- 103 min vs 146 +/- 108 and 175 +/- 92 min for groups A and B, respectively). There were no statistically significant differences in blood loss, hematocrit, or hemodynamic parameters among the groups. CONCLUSIONS: Early and adequate isotonic saline resuscitation of unanesthetized rats improved outcome despite continuing hemorrhage. The significantly lower mortality rate and increased survival time were not a result of transiently improved arterial pressure and did not correlate with blood loss. No significant bleeding increases were noted in the resuscitated groups.  相似文献   
104.
In search for cancer chemoprevention agents, seven new amide compounds have been synthesized. The structures have been determined based on spectral and chemical data. N-4-(ethoxycarbophenyl)-alpha-naphthamide and N-4-(ethoxycarbophenyl)-beta-naphthamide were shown to be 81% and 79% effective, respectively, for inducing different in HL-60 human promyelocytic leukemia cells at the concentration of 10(-5) mol/L in NBT tests.  相似文献   
105.
Twenty-three apparently normal untrained men aged 20--55 participated in a 4-month self-regulated training programme ending in a marathon run. Fasting plasma and lipoprotein lipid concentrations, adipose tissue lipoprotein lipase activity, anthropometric data, alcohol consumption, smoking habits, weekly mileage run and performance on a bicycle ergometer were recorded before and after the training period. Training induced an increase in high density lipoprotein cholesterol (HDL-C) concentration which was not directly related to concomitant decreases in mean very low density lipoprotein cholesterol (VLDL-C) concentration or mean total skinfold thickness. The degree of the changes in VLDL lipids and HDL-C levels were related to pretraining values, and changes in HDL-C and VLDL triglycerides (VLDL-TG) were also associated. Initial total skinfold thickness correlated inversely with the change in VLDL-TG levels during training. The pretaining concentration of VLDL-C was related to the corresponding value for HDL-C after training. The magnitude of exercise-induced changes in VLDL-C and HDL-C levels are more related to pre-training levels than to changes in measured exercise parameters, indices of obesity or adipose tissue lipoprotein lipase activity. However, the level of adiposity of subjects at the beginning of the study influenced the response of VLDL-TG levels to increased physical activity. The data suggest that VLDL contributes to the increase in HDL-C levels with exercise but is not the major source of the increment.  相似文献   
106.
A sensitive spectrophotometric micromethod was developed for estimation of ornithine decarboxylase (ODC) activity in animal tissues. Distinct increase in the enzymatic activity was found in regenerating and malignant liver tissues as well as in hepatomas G-27 and G-46 as compared with the corresponding tissues of control animals. The linear relationship between the optic density and content of dinitrophenyl putrescine was maintained over the range of 0 to 150 nmol per a sample. The ODC pH optimum was observed within the zone pH 6.4-6.8; it did not depend on the nature of the buffer, used for tissue homogenization. The recovery of putrescine added into the sample was equal to 102.97 +/- 2.22%. The method had an error less than 3%, its sensitivity was 0.1 nmol/sample and the reproducibility was about 100%.  相似文献   
107.
Glycogen Synthase Kinase-3 (GSK-3) was isolated from bovine heart tissue extracts by a procedure involving ammonium sulfate fractionation, followed by chromatography on phosphocellulose, Cibacron blue 3GA-agarose, DEAE-Sephacel, CM-Sepharose, heparin-agarose, myelin basic protein-Sepharose, and LiChrospher 1000 C00-. GSK-3 was identified by its activation of protein phosphatase-1i (PP-1i). The purified enzyme had a specific activity of 25,500 units of protein phosphatase-1i activated/mg protein. The enzyme is an asymmetric monomeric protein of 53 kDa. The molecular size and retention of activity after autophosphorylation indicated that the isolated enzyme was the GSK-3 alpha-isoform.  相似文献   
108.
Certain germline mutations (607Arg-Gln, 608Arg-Lys) in the androgen receptor gene have been associated with the occurrence of breast cancer in males suffering from partial androgen insensitivity. To assess whether somatic mutations in this gene could be detected in breast carcinoma, archival tumor tissue of males without clinical evidence of androgen insensitivity was screened for point mutations in the androgen receptor gene. DNA was retrieved by chloroform-phenol extraction from formalin-fixed, paraffin-embedded tissues. Exons 2-8 of the androgen receptor gene, encoding the DNA- and hormone-binding regions of the receptor, were amplified by polymerase chain reaction and subjected to nonisotopic single strand conformation assay (SSCA) to screen for point mutations. In the tumor DNA, no variations suggestive of mutations were encountered on SSCA. However, in a control patient with partial androgen insensitivity and predominantly female phenotype, the germline mutation 607Arg-Gln was identified in blood leukocyte DNA. Our results indicate that somatic mutations of the androgen receptor are not required for the development of male breast cancer. This, however, does not exclude an increased risk of breast carcinoma in patients with androgen insensitivity.  相似文献   
109.
Treatable malnutrition may occur in up to 25% of hospital patients, depending on the specialty concerned. Nutritional status may also deteriorate during a prolonged hospital stay. The management and prevention of malnutrition requires a climate in which hospital managers have a positive policy towards nutritional care, a screening system to identify the patients at risk, and appropriate protocols for action. Catering services need to be reorganized to address the problems of the sick, so that appropriate food is not only prepared but delivered in a way which makes it likely to be consumed. For the optimal management of artificial nutrition by the enteral or parenteral route, a skilled nutrition team is both necessary and cost-effective.  相似文献   
110.
The measurement of bone mineral density (BMD) using dual energy X-ray absorptiometry (DXA) provides an indicator of subsequent risk of hip fracture, but because of the significant overlap of measurements obtained from osteoporotic and control groups its predictive power is limited. The radiographic technique of Singh grading for the assessment of femoral osteoporosis utilizes information about the distribution of trabecular bundles, but the morphological information available in the DXA image has not previously been analysed. In this study of DXA images from 64 individuals (32 controls and 32 classified as osteoporotic) a subjective grading technique analogous to Singh grading is proposed, and quantitative measurements are made of image features corresponding to two of the categories. Discrimination was assessed using receiver operating characteristic (ROC) curves: the best discrimination was by spinal BMD (Az = 0.85 +/- 0.05) a performance equalled by one of the new parameters; the subjective grading method (Az = 0.79 +/- 0.07) performed as well as measurements of BMD in the femur. These results suggest that although the alternative measures do not improve on the discrimination possible using spinal BMD, morphological information from the hip itself may in the future have a place in the assessment of bone quality.  相似文献   
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